Instrument for checking the rate of time-piece movements



Aug. 26, 1958 F. MARTI ET AL 2,849,273

INSTRUMENT FOR CHECKING THE RATE OF TIME-PIECE MOVEMENTS Filed April 6, 1954 INVENTORS FRITZ MART! GEORGES BRAUNJCHWEIQ JEAN JCHAAD 8v M4% ATTORNEKS United States Patent Ofiice 2,849,273 Patented Aug. 26, 1958 INSTRUMENT FOR CHECKING THE RATE OF TIME-PIEQE MOVEMENTS Fritz Marti, Georges Braunschweig, and Jean Schaad, La Chaux-de-Fonds, Switzerland Application Aprii 6, 1954, Serial No. 421,364 2 Claims. (Cl. 346-78) This invention relates to instruments for checking the rate of time-piece movements and more particularly of watch and clock movements.

The invention has for its object to provide generally improved instruments of the type which comprises a synchron motor serving as a time standard and driving a rotary member provided with ribs, an electromagnet excitable by the amplified tick-tock or beats of the timepiece to be tested, and a striking-hammer controlled by the electromagnet and co-operating with an inking device to print on a recording band the successive points of intersection of the ribs with the striking-hammer.

According to an important feature of the invention, the recording mechanism comprising at least the inking device with its ribbon reversing device, the striking-hammer, the electrornagnet and a spring-loaded guide roller for the recording band is mounted between two braced spaced vertical flanges hinged by their one end and removably secured by their other end to the top plate of the instrument, so as to form a whole aggregate which is pivotable in order to facilitate setting of the recording band and changing of the inking ribbon.

In the accompanying drawings there is shown by way of example a preferred form of construction of the instrument embodying the invention.

In the drawings, Fig. 1 is a fragmentary view of the instrument showing the recording aggregate in side elevation; and

Fig. 2 is a top plan view thereof.

In the construction represented, the Figure l designates the top plate of the instrument below which there are mounted a synchron motor 31 and a rotary drum, 32, provided with helicoidal ribs 33 and driven by said motor. The plate 1 provides a guideway for a recording paper band 2 the feed movement of which is caused by the usual feed mechanism, not shown. The recording band is resiliently pressed against the plate 1 by a spring-loaded roller 3 (Fig. 1) equipped with a hand lever 4 (Fig. 2). Reference numbers 5 designate two spaced vertical flanges extending parallelly to each other which are made each of two pieces, namely a front piece 5a and a rear piece 5b; the front pieces 5a are nearer to one another than the rear pieces 51;. These flanges 5, which could also be made each of a single piece, are rigidly braced by means of cross-bars 6, 7, 8, 9 and are designed to support various members of the recording mechanism, namely:

an electromagnet 10 with its pole-pieces 11, a strikinghammer 12 with its armature 13, and the inking mechanism with the inking ribbon 18 and the ribbon reversing device which will be clearly described hereinafter.

Both the flanges 5 are hinged by the ends of their rear pieces 51; to the plate 1 by means of a pin 14 carried by two brackets 15 rigid with the plate 1. At the opposite end, the flanges 5 are removably secured to the plate 1 by the end portions of their front pieces 5a by means of two screws 16 screwed in said plate and equipped with coil springs 17 enabling the whole recording aggregate carried by the flanges 5 to be adjusted at the desired height. By loosening the screws 16, the recording aggregate can thus be pivoted or rocked rearwardly about the hinge 14 to facilitate setting of the recording paper band 2 and changing of the inking ribbon 18.

The inking ribbon 18 is reeled-up at both ends of its loop on two spools 19 and 20 rigidly connected with two arranged to alternately mesh with a pinion 23 and with a reversing gear 24 constantly meshing with each other. The spools 19 and 20 and their associated pinions 21, 22 are journalled between the flanges 25 of a first rocker pivoted about an axle 26 extending through the tubular brace 9. This brace is equipped with a freely rotatable sleeve serving as a guide roller for the lower side of the inking ribbon 18.

On the first rocker 25 there is journalled at 27 a second rocker constituted by two links 28 carrying between them a rotatable roller 29 designed to bear against either of the ribbon coils reeled-up on the spools 19 and 20. A coil spring 30 attached on the one side to the stud of the roller 29 and on the other side to a bracket rigid with the flange 5b at a point situated in vertical alignment with and above the axle 26 of the rocker 25, tends to press the roller 29 against the driving ribbon coil as long as the diameter of said coil does not reach the ultimate value at which the plane passing through the axis of the roller 29 and the rocking axis 27 of the second rocker 28 intersects also the rocking axis of the first rocker 25. Just as the driving ribbon coil reaches this value, the spring 30 swings the roller 29 against the other ribbon coil and the weight of this roller rocks in turn the first rocker 25 which carries the spools 19 and 20 and their associated pinions 21, 22, thus causing the one of said pinions 21, 22 which is associated with the empty spool to mesh with the corresponding driving gear 23 or 24. The inking ribbon becomes then reversed and the one spool which was driven becomes in turn the driving spool.

What we claim is:

1. In an instrument for checking the rate of time-piece movements; the combination of a top plate; a synchron motor serving as a time standard; a rotary member driven by said motor and provided with marking ribs mounted below said top plate; an electromagnet excitable by the amplified beats of the time-piece to be tested; a striking hammer controlled by said electromagnet; an inking device including an inking ribbon and a ribbon reversing mechanism cooperating with said striking hammer; a re cording band mounted on said top plate and cooperating with said inking device and striking hammer to record thereon the successive points of intersection of the marking ribs with the striking hammer; two spaced vertical flanges above said top plate; means for rigidly connecting said flanges together; there being a spring guided roller for said recording band between said flanges; means associated with said flanges for supporting therebetween said inking device, said electromagnet and said spring-loaded guide roller; means for hingedly connecting said flanges by the one end and for removably securing them by their other end to said top plate to form a pivotable recording unit whereby setting of the recording band and changing of the inking ribbon is facilitated.

2. In an instrument for checking the rate of time-piece movements of the character described, the combination of recording mechanism as claimed in claim 1, wherein the flanges supporting the pivotable recording unit are secured at their end carrying the striking-hammer by means of spring-loaded screws thereby enabling vertical adjustment of said unit.

pinions 22, 21 respectively,

References Cited in the file of this patent UNITED STATES PATENTS 852,850 Schmolinski May 7, 1907 941,130 Crook Nov. 23, 1909 1,757,012 Foote May 6, 1930 2,155,646 Fetter et a1. Apr. 25, 1939 2,259,309 Hibbard Oct. 14, 1941 2,280,613 Arey Apr. 21, 1942 2,421,781 Gibbs June 10, 1947 2,669,501 Young et a1 Feb. 16, 1954 

